AC electrophoretic mobility of individual microscale colloidal particles measured using holographic video microscopy

Toyokazu Ikeda, Haruka Eitoku, Yasuyuki Kimura

Research output: Contribution to journalArticle

Abstract

Electrophoretic mobility has been widely used to evaluate the zeta potential of individual colloidal particles, which governs the stability of colloidal dispersions. We demonstrated two experimental methods to measure the AC electrophoretic mobility μ of micron-sized single particles using holographic video microscopy. The three-dimensional position of the particle was estimated by reconstructing the light field from its two-dimensional holographic image, using the Rayleigh-Sommerfeld back-propagation method. In a planar electric field setup, the height dependence of the measured value of μ in the cell enables us to evaluate the actual value of μ, without interference from electroosmotic flow. In a vertical setup, the true value of μ can be directly evaluated by minimizing the influence of the electrode polarization, using a thick cell and a high-frequency electric field. The estimated values of μ obtained using both methods agree with that from conventional electrophoretic light scattering. We also evaluated the distribution of μ values within a colloidal dispersion.

Original languageEnglish
Article number153703
JournalApplied Physics Letters
Volume114
Issue number15
DOIs
Publication statusPublished - Apr 15 2019

All Science Journal Classification (ASJC) codes

  • Physics and Astronomy (miscellaneous)

Fingerprint Dive into the research topics of 'AC electrophoretic mobility of individual microscale colloidal particles measured using holographic video microscopy'. Together they form a unique fingerprint.

  • Cite this